The value of chest roentgenography in the diagnosis of pneumothorax after thoracentesis

Ultrasound-guided interventional radiology procedures in the chest

Ultrasonography is a very good tool for guiding different interventional procedures in the chest. It is the ideal technique for managing conditions involving the pleural space, and it makes it possible to carry out procedures such as thoracocentesis, biopsies, or drainage. In the lungs, only lesions in contact with the costal pleura are accessible to ultrasound-guided interventions. In this type of lung lesions, ultrasound is as effective as computed tomography to guide interventional procedures, but the rate of complications and time required for the intervention are lower for ultrasound-guided procedures.

Is routine chest radiography necessary after ultrasonography-guided catheter thoracostomy?

INTRODUCTION

Many institutions still perform routine chest radiography (CXR) after tube thoracostomies despite current guidelines suggesting that this is not necessary for simple cases. We aimed to evaluate the usefulness of routine CXR following ultrasonography-guided catheter thoracostomies for the detection of complications of symptomatic pleural effusions in hospitalised patients.

METHODS

This was a retrospective review of 2,032 ultrasonography-guided thoracostomies on hospitalised patients with symptomatic effusions at a single institution from April 2012 to May 2015. The aetiology of effusions was not systemically registered, but patient demographics, procedural details and clinical outcomes were collected. Data was analysed using descriptive statistics and chi-square test. Generalised estimating equation analysis was performed to assess the relationship between CXR findings and complications while controlling for age.

RESULTS

Out of 2,032 CXRs, 92.96% (n = 1,889) were normal, 5.81% (n = 118) showed pneumothorax and 1.23% (n = 25) showed catheter kinking. 99 pneumothoraces and 24 kinked catheters were detected in the first hour post procedure. 97.40% (n = 115) of patients with pneumothorax were stable or had minor complications, such as a vasovagal event. 0.20% (n = 4) of the cases had a serious complication following chest drain insertion, resulting in cardiovascular collapse. There was no significant relationship between CXR results and occurrence of complications (p = 0.244). Amount of fluid drained or side of insertion did not affect the clinical outcome.

CONCLUSION

Routine use of CXR after tube thoracostomy did not significantly change patient management, which was concordant with recent guidelines. Instead, adverse clinical outcomes or procedural factors should guide investigations.

Utility of pleural effusion drainage in the ICU: An updated systematic review and META-analysis

PURPOSE

The effects on the respiratory or hemodynamic function of drainage of pleural effusion on critically ill patients are not completely understood. First outcome was to evaluate the PiO₂/FiO₂ (P/F) ratio before and after pleural drainage.

SECONDARY OUTCOMES

evaluation of A-a gradient, End-Expiratory lung volume (EELV), heart rate (HR), mean arterial pressure (mAP), left ventricular end-diastolic volume (LVEDV), stroke volume (SV), cardiac output (CO), ejection fraction (EF), and E/A waves ratio (E/A). A tertiary outcome: evaluation of pneumothorax and hemothorax complications.

MATERIALS AND METHODS

Searches were performed on MEDLINE, EMBASE, COCHRANE LIBRARY, SCOPUS and WEB OF SCIENCE databases from inception to June 2018 (PROSPERO CRD42018105794).

RESULTS

We included 31 studies (2265 patients). Pleural drainage improved the P/F ratio (SMD: -0.668; CI: -0.947-0.389; p < .001), EELV (SMD: -0.615; CI: -1.102-0.219; p = .013), but not A-a gradient (SMD: 0.218; CI: -0.273-0.710; p = .384). HR, mAP, LVEDV, SV, CO, E/A and EF were not affected. The risks of pneumothorax (proportion: 0.008; CI: 0.002-0.014; p = .138) and hemothorax (proportion: 0.006; CI: 0.001-0.011; p = .962) were negligible.

CONCLUSIONS

Pleural effusion drainage improves oxygenation of critically ill patients. It is a safe procedure. Further studies are needed to assess the hemodynamic effects of pleural drainage.

Recommendations on the Use of Ultrasound Guidance for Adult Thoracentesis: A Position Statement of the Society of Hospital Medicine

Executive Summary: 1) We recommend that ultrasound should be used to guide thoracentesis to reduce the risk of complications, the most common being pneumothorax. 2) We recommend that ultrasound guidance should be used to increase the success rate of thoracentesis. 3) We recommend that ultrasound-guided thoracentesis should be performed or closely supervised by experienced operators. 4) We suggest that ultrasound guidance be used to reduce the risk of complications from thoracentesis in mechanically ventilated patients. 5) We recommend that ultrasound should be used to identify the chest wall, pleura, diaphragm, lung, and subdiaphragmatic organs throughout the respiratory cycle before selecting a needle insertion site. 6) We recommend that ultrasound should be used to detect the presence or absence of an effusion and approximate the volume of pleural fluid to guide clinical decision-making. 7) We recommend that ultrasound should be used to detect complex sonographic features, such as septations, to guide clinical decision-making regarding the timing and method of pleural drainage. 8) We suggest that ultrasound be used to measure the depth from the skin surface to the parietal pleura to help select an appropriate length needle and determine the maximum needle insertion depth. 9) We suggest that ultrasound be used to evaluate normal lung sliding pre- and postprocedure to rule out pneumothorax. 10) We suggest avoiding delay or interval change in patient position from the time of marking the needle insertion site to performing the thoracentesis. 11) We recommend against performing routine postprocedure chest radiographs in patients who have undergone thoracentesis successfully with ultrasound guidance and are asymptomatic with normal lung sliding postprocedure. 12) We recommend that novices who use ultrasound guidance for thoracentesis should receive focused training in lung and pleural ultrasonography and hands-on practice in procedural technique. 13) We suggest that novices undergo simulation-based training prior to performing ultrasound-guided thoracentesis on patients. 14) Learning curves for novices to become competent in lung ultrasound and ultrasound-guided thoracentesis are not completely understood, and we recommend that training should be tailored to the skill acquisition of the learner and the resources of the institution.

Complications of thoracentesis: incidence, risk factors, and strategies for prevention

PURPOSE OF REVIEW

Although thoracentesis is generally considered safe, procedural complications are associated with increased morbidity, mortality, and healthcare costs. In this article, we review the risk factors and prevention of the most common complications of thoracentesis including pneumothorax, bleeding (chest wall hematoma and hemothorax), and re-expansion pulmonary edema.

RECENT FINDINGS

Recent data support the importance of operator expertise and the use of ultrasound in reducing the risk of iatrogenic pneumothorax. Although coagulopathy or thrombocytopenia and the use of anticoagulant or antiplatelet medications have traditionally been viewed as contraindications to thoracentesis, new evidence suggests that patients may be able to safely undergo thoracentesis without treating their bleeding risk. Re-expansion pulmonary edema, a rare complication of thoracentesis, is felt to result in part from the generation of excessively negative pleural pressure. When and how to monitor changes in pleural pressure during thoracentesis remains a focus of ongoing study.

SUMMARY

Major complications of thoracentesis are uncommon. Clinician awareness of risk factors for procedural complications and familiarity with strategies that improve outcomes are essential components for safely performing thoracentesis.

Interventional procedures in the chest

Many thoracic conditions will require an interventional procedure for diagnosis and/or treatment. For this reason, radiologists need to know the indications and the technique for each procedure. In this article, we review the various interventional procedures that radiologists should know and the indications for each procedure. We place special emphasis on the potential differences in the diagnostic results and complications between fine-needle aspiration and biopsy. We also discuss the indications for radiofrequency ablation of lung tumors and review the concepts related to the drainage of pulmonary abscesses. We devote special attention to the management of pleural effusion, covering the indications for thoracocentesis and when to use imaging guidance, and to the protocol for pleural drainage. We also discuss the indications for percutaneous treatment of pericardial effusion and the possible complications of this treatment. Finally, we discuss the interventional management of mediastinal lesions and provide practical advice about how to approach these lesions to avoid serious complications.

Should patients be advised not to fly post thoracentesis?

Air travel poses a risk to patients with a pneumothorax due to in-flight pressure changes and guidance is available providing advice on air travel in patients with a pneumothorax. Pneumothorax is a recongnised complication of pleural thoracentesis, however chest radiographs have been shown to have limited sensitivity in diagnosing pneumothoraces and small pneumothoraces may not be recognised. There is, therefore a risk post thoracentesis, of exacerbating an unrecognised pneumothorax by air travel. This case outlines the presentation of a 55 year old lady, with a normal chest radiograph after an uncomplicated simple needle aspiration for a pleural effusion, who developed a large pneumothorax during air travel.

Ultrasonography as a guide during vascular access procedures and in the diagnosis of complications

Vascular access used in the treatment of patients involves central and peripheral vein accesses and arterial accesses. Catheterization of central veins is widely used in clinical practice; it is a necessary part of the treatment of patients in various settings. The most commonly involved vessels are the internal jugular, subclavian, and femoral veins. The mechanical, infectious, and thrombotic complications of central venous catheterization are markedly reduced when the procedure is performed with real-time ultrasound guidance or (to a slightly lesser extent) ultrasound assistance. Ultrasound guidance is also used to create peripheral venous accesses, for catheterization of peripheral veins and for peripheral insertion of central venous catheters. In this setting, it increases the catheterization success rate, especially during difficult procedures (e.g., obese patients, children) and reduces complications such as catheter-related infections and venous thrombosis. Arterial cannulation is used for invasive monitoring of arterial pressure and for access during diagnostic or therapeutic procedures. Ultrasound guidance reduces the risk of catheterization failure and complications. It is especially useful for arterial catheterization procedures performed in the absence of a palpable pulse (e.g., patient in shock, ECMO). Imaging support is being used increasingly to facilitate the creation of vascular accesses under difficult conditions, in part because of the growing use of ultrasonography as a bedside procedure. In clinical settings where patients are becoming increasingly vulnerable as a result of advanced age and/or complex disease, the possibility to reduce the risks associated with these invasive procedures should motivate clinicians to acquire the technical skills needed for routine use of sonographic support during vascular access procedures.

Verification of correct central venous catheter placement in the emergency department: comparison between ultrasonography and chest radiography

In 210 consecutive patients undergoing emergency central venous catheterization, we studied whether an ultrasonography examination performed at the bedside by an emergency physician can be an alternative method to chest X-ray study to verify the correct central venous catheter placement, and to identify mechanical complications. A prospective, blinded, observational study was performed, from January 2009 to December 2011, in the emergency department of a university-affiliated teaching hospital. Ultrasonography interpretation was completed during image acquisition; ultrasound scan was performed in 5 ± 3 min, whereas the time interval between chest radiograph request and its final interpretation was 65 ± 74 min p < 0.0001. We found a high concordance between the two diagnostic modalities in the identification of catheter position (Kappa = 82 %, p < 0.0001), and their ability to identify a possible wrong position showed a high correlation (Pearson's r = 0.76 %, p < 0.0001) with a sensitivity of 94 %, a specificity of 89 % for ultrasonography. Regarding the mechanical complications, three iatrogenic pneumothoraces occurred, all were correctly identified by ultrasonography and confirmed by chest radiography (sensitivity 100 %). Our study showed a high correlation between these two modalities to identify possible malpositioning of a catheter resulting from cannulation of central veins, and its complications. The less time required to perform ultrasonography allows earlier use of the catheter for the administration of acute therapies that can be life-saving for the critically ill patients.

Common procedures in internal medicine: improving knowledge and minimizing complications

Internal medicine physicians have long been trained with the skills, knowledge, and attitudes to become proficient at certain medical procedures. Specifically, the lumbar puncture, paracentesis, thoracentesis, and central venous catheter placement are common medical procedures encountered during residency. Despite recent changes that no longer require documented competency in procedure performance, many residents and their attending supervisors continue to perform these procedures on a regular basis. In private practice many internists care for patients requiring these procedures. This review will summarize basic steps followed in these 4 medical procedures and highlight methods to minimize associated complications.

Bedside ultrasound in pediatric critical care: a review

OBJECTIVE

Bedside ultrasound, as performed by the intensivist, is gaining in popularity and has become a powerful tool to understand the physiological state of the critically ill patient and to decrease procedural risks. This review assesses clinical applications of bedside ultrasound in the pediatric intensive care unit.

DESIGN

A literature review was conducted to identify English language studies in Pubmed as of June, 2010, using combinations of the following search terms: 'pediatric,' 'ultrasound,' 'critical care,' and 'intensive care.' Examination of reference lists of these studies yielded additional studies. Studies were reviewed by both authors.

SETTING

Intensive care unit, emergency department, or operating rooms, as relevant to application of bedside ultrasound in the pediatric intensive care unit.

PATIENTS/SUBJECTS

Pediatric patients (age 0-18 yrs) with adult patients (>18 yrs) in relevant studies utilizing bedside ultrasound by the treating clinician.

INTERVENTIONS

Bedside ultrasound by treating clinician.

MEASUREMENTS

Variable, per individual studies. MAIN RESULTS/CONCLUSIONS: Bedside ultrasound, as practiced by the pediatric intensivist, has the potential to improve pediatric critical care medicine, but data supporting its use is limited. Further studies are needed to explore applications, with specific emphasis on the training and experience of ultrasound operators. There is a need for a standardized educational curriculum, and questions remain as to the optimal mode of education and quality assurance of ultrasound operators.

Large-volume thoracentesis and the risk of reexpansion pulmonary edema

BACKGROUND

To avoid reexpansion pulmonary edema (RPE), thoracenteses are often limited to draining no more than 1 L. There are, however, significant clinical benefits to removing more than 1 L of fluid. The purpose of this study was to define the incidence of RPE among patients undergoing large-volume (> or = 1 L) thoracentesis.

METHODS

One hundred eighty-five patients undergoing large-volume thoracentesis were included in this study. The volume of fluid removed, absolute pleural pressure, pleural elastance, and symptoms during thoracentesis were compared in patients who did and did not experience RPE.

RESULTS

Of the 185 patients, 98 (53%) had between 1 L and 1.5 L withdrawn, 40 (22%) had between 1.5 L and 2 L withdrawn, 38 (20%) had between 2 L and 3 L withdrawn, and 9 (5%) had more than 3 L withdrawn. Only 1 patient (0.5%, 95% confidence interval: 0.01% to 3%) experienced clinical RPE. Four patients (2.2%, 95% confidence interval: 0.06% to 5.4%) had radiographic RPE (diagnosed only on postprocedure imaging without clinical symptoms). The incidence of RPE was not associated with the absolute change in pleural pressure, pleural elastance, or symptoms during thoracentesis.

CONCLUSIONS

Clinical and radiographic RPE after large-volume thoracentesis is rare and independent of the volume of fluid removed, pleural pressures, and pleural elastance. The recommendation to terminate thoracentesis after removing 1 L of fluid needs to be reconsidered: large effusions can, and should, be drained completely as long as chest discomfort or end-expiratory pleural pressure less than -20 cm H2O does not develop.

Chest radiographs after removal of chest drains in neonates: clinical benefit or common practice?

BACKGROUND

Chest drain insertion is a common procedure in neonatal care. Routine radiography after removal of chest drains increases radiation exposure, handling and cost, but there are few data proving clinical benefit.

OBJECTIVES

To review current practice and determine the yield of routinely obtained chest radiographs (CXR).

METHODS

A retrospective chart review of all infants undergoing removal of chest tubes in a single tertiary neonatal unit in New Zealand between January 1998 and July 2004 was performed.

RESULTS

In total, 119 infants were identified, from the database, to have a chest drainage performed. In 19 cases, the procedure was needle aspiration or the drain was removed outside of our unit, hence these were excluded. The remaining 100 patients with 110 episodes of chest drain removal after 174 chest tube insertions were analysed. In asymptomatic infants, routine radiography showed some reaccumulation of air in nine of 35 cases of pneumothorax or of fluid in two of the five cases of pleural effusion, but chest tube reinsertion was not required. In the 12 clinically symptomatic infants, chest tubes were reinserted in five cases (four reaccumulations of pneumothorax and one pleural effusion), and one infant had symptomatic right upper lobe collapse. In the remaining infants, there were no abnormalities on CXR accounting for deterioration.

CONCLUSIONS

Given the low yield for routine radiography after chest drain removal, we suggest that close observation is likely to detect clinically relevant recurrence of pneumothorax.

[Failures and complications of thoracic drainage]

BACKGROUND/AIM

Thoracic drainage is a surgical procedure for introducing a drain into the pleural space to drain its contents. Using this method, the pleura is discharged and set to the physiological state which enables the reexpansion of the lungs. The aim of the study was to prove that the use of modern principles and protocols of thoracic drainage significantly reduces the occurrence of failures and complications, rendering the treatment more efficient.

METHODS

The study included 967 patients treated by thoracic drainage within the period from January 1, 1989 to June 1, 2000. The studied patients were divided into 2 groups: group A of 463 patients treated in the period from january 1, 1989 to December 31, 1994 in whom 386 pleural drainage (83.36%) were performed, and group B of 602 patients treated form January 1, 1995 to June 1, 2000 in whom 581 pleural drainage (96.51%) were performed. The patients of the group A were drained using the classical standards of thoracic drainage by the general surgeons. The patents of the group B, however, were drained using the modern standards of thoracic drainage by the thoracic surgeons, and the general surgeons trained for this kind of the surgery.

RESULTS

The study showed that better results were achieved in the treatment of the patients from the group B. The total incidence of the failures and complications of thoracic drainage decreased from 36.52% (group A) to 12.73% (group B). The mean length of hospitalization of the patients without complications in the group A was 19.5 days versus 10 days in the group B. The mean length of the treatment of the patients with failures and complications of the drainage in the group A was 33.5 days versus 17.5 days in the group B.

CONCLUSION

The shorter length of hospitalization and the lower morbidity of the studied patients were considered to be the result of the correct treatment using modern principles of thoracic drainage, a suitable surgical technique, and a careful follow-up of the patients.

Accuracy of transthoracic sonography in excluding post-interventional pneumothorax and hydropneumothorax. Comparison to chest radiography

OBJECTIVE

Transthoracic sonography (TS) has evolved as an important imaging technique for diagnosing pleural and pulmonary conditions. However, the value of TS in either excluding or diagnosing pneumothorax is still under debate. This study was conducted to examine whether TS could replace chest radiography for the diagnosis of post-interventional pneumothorax and hydropneumothorax.

METHODS

53 patients (21 females, 32 males; median age 64 years, range 37-94 years), 35 of whom underwent transbronchial biopsy (TBB) and 18 patients who had an ultrasound-guided chest tube placement (U-GCTP) were enrolled in the study. TS was performed three hours after either TBB or removal of a chest tube, followed by postero-anterior chest radiograph (CRX). If any discrepancy between TS, the clinical presentation and the CRX became apparent, either a lateral CRX or a computed tomography (CT) of the thorax was performed. TS was assessed according to the presence of the following criteria: (1) "gliding sign" of the pleural line, (2) comet tail artifacts, (3) reverberation artifacts, (4) air/fluid mirror, (5) hyperechoic reflectors within the pleural effusion and (6) "lung point".

RESULTS

In four out of the 53 patients (7.5%) a post-interventional pneumothorax or hydropneumothorax occurred. One out of the 35 patients (2.9%) developed a pneumothorax after TBB, requiring chest tube placement. Three patients (16.7%) developed a hydropneumothorax due to U-GCTP which was detected by sonography but was missed by postero-anterior CRX in one patient. The sensitivity, specificity and accuracy of TS were 100% in excluding post-interventional pneumothorax/hydropneumothorax.

CONCLUSION

TS is a cost-effective and safe bed-side-method, allowing for an immediate exclusion or diagnosis of post-interventional pneumothorax/hydropneumothorax in patients who have undergone TBB or U-GCTP. Thus, these preliminary results suggest that CXR may only be required in patients with pneumothorax diagnosed by TS in order to assess its extension or to exclude any discrepancy between the TS-result and the clinical presentation.

Emergent ultrasound interventions

The interventionist can perform many emergent procedures with ultrasound guidance, because of its real-time, multiplanar imaging capability and portability. With the use of color Doppler, additional important information, such as aberrant vessels, can be ascertained to help plan needle trajectory. Ultrasound is also useful for nonemergent procedures, such as biopsies. All interventionists are encouraged to be facile with the use of ultrasound.

Ultrasound-guided thoracentesis: is it a safer method?

STUDY OBJECTIVES

The objectives of this study are as follows: (1) to determine the incidence of complications from thoracentesis performed under ultrasound guidance by interventional radiologists in a tertiary referral teaching hospital; (2) to evaluate the incidence of vasovagal events without the use of atropine prior to thoracentesis; and (3) to evaluate patient or radiographic factors that may contribute to, or be predictive of, the development of re-expansion pulmonary edema after ultrasound-guided thoracentesis.

DESIGN

Prospective descriptive study.

SETTING

Saint Thomas Hospital, a tertiary referral teaching hospital in Nashville, TN.

PATIENTS

All patients referred to interventional radiology for diagnostic and/or therapeutic ultrasound-guided thoracentesis between August 1997 and September 2000.

RESULTS

A total of 941 thoracenteses in 605 patients were performed during the study period. The following complications were recorded: pain (n = 25; 2.7%), pneumothorax (n = 24; 2.5%), shortness of breath (n = 9; 1.0%), cough (n = 8; 0.8%), vasovagal reaction (n = 6; 0.6%), bleeding (n = 2; 0.2%), hematoma (n = 2; 0.2%), and re-expansion pulmonary edema (n = 2; 0.2%). Eight patients with pneumothorax received tube thoracostomies (0.8%). When > 1,100 mL of fluid were removed, the incidence of pneumothorax requiring tube thoracostomy and pain was increased (p < 0.05). Fifty-seven percent of patients with shortness of breath during the procedure were noted to have pneumothorax on postprocedure radiographs, while 16% of patients with pain were noted to have pneumothorax on postprocedure radiographs. Vasovagal reactions occurred in 0.6% despite no administration of prophylactic atropine. Re-expansion pulmonary edema complicated 2 of 373 thoracenteses (0.5%) in which > 1,000 mL of pleural fluid were removed.

CONCLUSIONS

The complication rate with thoracentesis performed by interventional radiologists under ultrasound guidance is lower than that reported for non-image-guided thoracentesis. Premedication with atropine is unnecessary given the low incidence of vasovagal reactions. Re-expansion pulmonary edema is uncommon even when > 1,000 mL of pleural fluid are removed, as long as the procedure is stopped when symptoms develop.

Management of pneumothorax and barotrauma: current concepts

Pneumothorax can be spontaneous, traumatic or iatrogenic. Pneumothorax ex vacuo, sports-related pneumothorax and barotrauma unrelated to mechanical ventilation are interesting and newer entities. Management consists of getting rid of the air and prevention of recurrence of pneumothorax.

Ultrasonic examination: an alternative to chest radiography after central venous catheter insertion?

We evaluated ultrasonic examination as a diagnostic tool for catheter misplacement and pneumothorax after central venous catheter insertion. Physicians in the intensive care unit (ICU) performed the ultrasonic examinations, and the results were compared with those of chest radiography. Eighty-five central venous catheters (70 subclavian and 15 internal jugular) were inserted into 81 patients; 10 misplacements and one pneumothorax occurred. Ultrasonic examination feasibility was 99.6%. The only pneumothorax and all misplacements except one were diagnosed by ultrasound. Taking into consideration misplacements and pneumothorax research, ultrasonic examination did not give any false positive results. The mean time of the entire ultrasonic examination was 6.8 +/- 3.5 min, whereas 80.3 +/- 66.7 min were needed for the radiography (p < 0.0001). This study has suggested that ultrasonic diagnosis of catheter misplacement and pneumothorax related to central venous catheterization is a rapid and accurate method that can be easily performed by ICU physicians.